Driving device and an electric motorcycle driving system using the driving device

ABSTRACT

The present invention provides a driving device and an electric motorcycle driving system using the driving device. Said driving device comprises a shaft, a pulley disk assembly configured on the shaft, and a motor. The motor is an outer rotor or inner rotor motor. One pulley disk of the pulley disk assembly is connected to one end of the outer rotor sleeve or the inner rotor of the motor, so it can be driven by the outer rotor sleeve or the inner rotor and rotate or move around the shaft; furthermore, an electric motorcycle driving system can use the driving device to connect with a battery and a stepless speed change mechanism, so as to use the electric power of the battery to operate the stepless speed change mechanism, and to consequently enhance the performance of speed and torque output of the electric motorcycles.

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates generally to an electric motorcycle, andmore particularly to a driving device and an electric motorcycle drivingsystem using the driving device.

2. Description of Related Art

To meet the demands of environment protection and energy saving,electric motorcycles are becoming more and more popular than thetraditional gasoline motorcycles. The energy used by electricmotorcycles is electric power, which features no waste gas discharge andno noise pollution comparing to the engine-driven gasoline motorcycles.However, the speed of electric motorcycles will be limited by therotational speed and power of the motor itself. Because the motoroutputs a low torque under a low speed, and a high torque under a highspeed, it is unable to meet the requirement for low speed and hightorque. Under a high speed, the motor consumes considerable electricpower. Also, as it has no speed change function, the performance ofelectric motorcycles still falls behind the gasoline motorcycles usingthe continuously variable transmission (CVT). Secondly, as the electricmotorcycles have limited inner space to house the motor and battery,there is limitation for motor installation position and driving mode,which further affects the performance of electric motorcycles.

In recent years, there are some kinds of electric motorcycles providedwith continuously variable transmission (CVT) or automatic speed changesystems to enhance the performance. Although the electric motorcycleswith continuously variable transmission (CVT) or automatic speed changesystems offer better performance than the traditional electricmotorcycles, they have bigger sizes and their rotational speed is stilllimited by the power design of the motor.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a drivingdevice and an electric motorcycle driving system using the drivingdevice. By combining a motor and a pulley disk assembly, it considerablyreduces the size and enhance the flexibility to use the inner space ofthe electric motorcycle, and it only uses the centrifugal forcegenerated by the rotation of the motor to toss out the pulley roller tochange the overlapping area between the permanent magnet and stator coilinside the motor and change the rotational speed of the motor.

Therefore, to achieve the afore-mentioned objective, the presentinvention provides a driving device, which comprises: a motor andcomponents of an outer rotor sleeve and a stator coil provided insidethe outer rotor sleeve. The inner wall of the outer rotor sleeve isprovided with a plurality of permanent magnets; a pulley disk assembly,including a pulley disk, a plurality of pulley rollers on one substrateof the pulley disk and inside the pulley disk. The pulley disk isconnected to one end of the outer rotor sleeve and is movable relativeto the substrate. The substrate is located inside the outer rotorsleeve; a shaft, connected to the substrate and going through the outerrotor sleeve and the pulley disk. The outer rotor sleeve and the pulleydisk can rotate and move relative to the shaft.

In addition, the present invention further provides an electricmotorcycle driving system using the driving device, which comprises abattery; a stepless speed change mechanism comprising a fan blade disc,an open-close disc, a clutch, and a belt connecting between the fanblade disc and the open-close disc. The open-close disc and clutch isconnected with the wheel of the electric motorcycle; The driving deviceis connected with the battery and the stepless speed change mechanism,so as to use the electric power of the battery to operate the steplessspeed change mechanism. The motor is electrically connected with thebattery. The fan blade disc is configured on one side of the pulleydisk. One end of the belt is wound between the fan blade disc and thepulley disk.

Furthermore, the present invention provides a driving device, whichcomprises a shaft; a pulley disk assembly, configured on the shaft in arotatable manner, comprising a relative pulley disk, a substrate and aplurality of pulley rollers between the pulley disk and the substrate.The pulley disk can move along the shaft; a motor, comprising an innerrotor and such components as a stator coil configured on the peripheryof the inner rotor. The inner rotor is connected to the pulley disk, andits periphery is configured with a plurality of permanent magnetscorresponding to the stator coil.

BRIEF DESCRIPTION OF THE DRAWINGS

Multiple preferred embodiments are provided below to describe thepresent invention in more detail with the accompanied drawings:

FIG. 1 is a partial sectional view of a preferred embodiment of thepresent invention.

FIG. 2 is an operational view of a preferred embodiment of the presentinvention, showing the displacement of the pulley disk, and tossing-outof the pulley rollers.

FIG. 3 is a diagram of an electric motorcycle driving system of anotherpreferred embodiment of the present invention.

FIG. 4 is a partial sectional view of another preferred embodiment ofthe present invention.

FIG. 5 is an operational view of another preferred embodiment of thepresent invention, showing the displacement of the pulley disk, andtossing-out of the pulley rollers.

DETAILED DESCRIPTION OF THE INVENTION

Firstly, referring to FIG. 1, the driving device 10 of a preferredembodiment of the present invention comprises a motor 12, a pulley diskassembly 14 and a shaft 16.

The motor 12, which is a permanent-magnet brushless outer rotor motor,comprises an outer rotor sleeve 22 and such stator-related components(e.g. silicon steel sheet) like coils configured inside the outer rotorsleeve 22. The outer rotor sleeve 22 comprises a cylinder 26 with twoopen ends. The inner wall of the cylinder 26 is configured with a firstsection 30 and second section 32 with different inner diameters. Thejoining part between the first section and second section is formed as astage 34. The inner diameter of the first section is larger than that ofthe second section 32. Furthermore, the inner wall of the second section32 is provided with a plurality of permanent magnets 121, which areconfigured on the inner wall of the second section 32 in an N-S-N-Sarrangement adopting the 12-groove 14-pole electric motor design. Thecomposition of the permanent magnets 121 and stator coils 122 on theinner wall of the outer rotor sleeve 22 are similar to brushless outerrotor motor, and are not detailed here.

The pulley disk assembly 14 is a pulley disk assembly of continuouslyvariable transmission (CVT), comprising a pulley disk 36 covering asubstrate 38 of the pulley disk 36 and a plurality of pulley rollers 40configured inside the pulley disk 36. The pulley disk 36 is connected toone end of the outer rotor sleeve 22 and is movable relative to thesubstrate 38. The substrate 38 is located on the inner side of the outerrotor sleeve 22.

The shaft 16 is connected to the substrate 38 and goes through the outerrotor sleeve 22 and the pulley disk 36. The related components likestator coil 122 of the motor 12 are configured on the shaft 16. Theouter rotor sleeve 22 and pulley disk 36 can rotate and move relative tothe shaft 16.

In addition, the driving device 10 further comprises a contacting plate18, which is fixed on the shaft 16 and located inside the outer rotorsleeve 22, and is spaced with the stage 34 with some distancecorresponding to the substrate 38, so as to prevent the componentsinside the motor 12 like stator coil 122 from being frictioned anddamaged by the substrate 38 during the rotation of the pulley diskassembly 14.

Based on the above, the driving device 10 of the present invention hasthe following operational mode and characteristics:

When the motor 12 is operating, the outer rotor sleeve 22 can rotate anddrive the pulley disk 36 to rotate simultaneously. Each pulley roller 40will be tossed out under the centrifugal force generated by therevolving pulley disk 36. Higher rotational speed of the outer rotorsleeve 22 will cause a higher centrifugal force from the pulley disk 36to toss out the pulley rollers 40, consequently pushing the pulley disk36 to move outward relative to the substrate 38. In this way, the outerrotor sleeve 22 will also be caused to move (the distance between thestage 34 and the contacting plate 18 is for the displacement), as shownin FIG. 2, so that the relative positions of the outer rotor sleeve 22and related components like stator coil 122 will be changed (changingthe overlapping area between the permanent magnets 121 and stator coil122 inside the outer rotor sleeve 22), and consequently, the rotationalspeed of the outer rotor sleeve 22 will be changed.

From the above, it is known that, during operation of the drivingdevice, the centrifugal force generated by the revolving pulley disk cantoss out the pulley rollers inside it, and the tossed-out pulley rollerswith appropriate weights can push the pulley disk to cause adisplacement of the outer rotor sleeve, and change the overlapping areabetween the permanent magnets and stator coil inside the outer rotorsleeve, and consequently change the rotational speed of the outer rotorsleeve. In another word, the driving device can use a mechanicaloperation to change the rotational speed of the motor.

In addition, the driving device 10 can be applied in the driving systemof electric motorcycles. Referring to FIG. 3, which depicts the drivingsystem 50 of electric motorcycles of a preferred embodiment of thepresent invention, the system comprises a driving device 10, and furthercomprises a battery 52 and a stepless speed change mechanism 54. Thebattery 52 is electrically connected to the motor 12. The stepless speedchange mechanism 54 is the continuously variable transmission (CVT) ofconventional motorcycles, and comprises a fan blade disc 56, anopen-close disc 58, a clutch 59 and a belt 60 connecting between the fanblade disc 56 and the open-close disc 58. Its composition is notdetailed here. The fan blade disc 56 is configured on one side of thepulley disk 36. The open-close disc 58 and clutch 59 are connected tothe wheel of the electric motorcycle. One end of the belt 60 is woundbetween the fan blade disc 56 and the pulley disk 36.

In this way, the battery 52 can supply the electric power to run themotor 12. When the motor 12 is operating, the stepless speed changemechanism 54 can drive the electric motorcycle to run. As the steplessspeed change mechanism 54 is a mechanical automatic speed change system,it will automatically and mechanically adjust the rotational speed andtorque of the load to obtain the effect of gear differential and enhancethe rotational speed and torque.

In detail, during a low speed, as the pulley disk 36 has nodisplacement, the perimeter of the front end of the belt 60 is small andthat of the back end is large. In this circumstance, the motor 12 candrive the belt 60 to output a high torque, with no worry of insufficienttorque. On the other hand, when the speed of the motor 12 is raised, thepulley rollers 40 inside the pulley disk 36 will be tossed out under thecentrifugal force, causing a displacement of the pulley disk 36, thebelt 60 will have a front end with larger perimeter and back end withsmaller perimeter. The perimeter difference between the front end andback end of the belt 60 will generate a higher speed output.

Based on this, the electric motorcycle driving system 50 does not haveto consider a balance point between the torque and rotational speed ofthe motor 12, and only needs to find ways to enhance the rotationalspeed of the motor 12, while the torque can be enhanced through thedriving device 10 and the stepless speed change mechanism 54.

In addition, referring to FIG. 4, showing the driving device 70 ofanother preferred embodiment of the present invention, the compositionof the embodiment is roughly the same as the driving device 70, butdiffers in that: the motor 72 is in the style of a permanent-magnetbrushless inner rotor motor, and the inner rotor 74 is connected to thepulley disk 76. In this way, when the motor 72 is operating, the innerrotor 74 can rotate under the excitation between the stator coil 77 andthe permanent magnets 78, and the pulley disk 76 can also rotatesimultaneously with the inner rotor 74. Therefore, the pulley rollers 80will be tossed out by the centrifugal force generated by the revolvingpulley disk 76. When the rotational speed of the inner rotor 74 ishigher, the pulley disk 76 will cause a larger centrifugal force to tossout the pulley rollers 80, pushing the pulley disk 76 to move outward.Consequently, the inner rotor 74 will also be driven to move, as shownin FIG. 5, causing a change to the relative positions of the inner rotor74 and such related components as the stator coil 77 (changing theoverlapping area between the permanent magnets 78 and the stator coil 77to obtain a weak magnetic effect), and changing the rotational speed ofthe inner rotor 74. Secondly, during operation of the motor 72, thestator coil 77 will heat up. As it is located outside the inner rotor74, heat radiation is more convenient, and heat dissipation is moreefficient.

Additionally, the driving device 70 can also be used as the wheel motorfor motorcycles. In application, the inner rotor 74 is connected to oneend of the pulley disk 76 connecting the wheel rim, while the casing 82of the driving device 70 is fitted on the motorcycle body; in his way,when the inner rotor 74 rotates, it can directly drive the wheel of themotorcycle to run.

From the above, it is known that the driving device and the electricmotorcycle driving system using the driving device provided by thepresent invention adopt a totally new structure with the motor and thepulley disk assembly, which considerably reduces the size and meanwhileenhances the flexibility of space utilization of the electricmotorcycle. Moreover, the new structure can change the overlapping areabetween the permanent magnets in the inner or outer rotor sleeve and thestator coil without using any electric control means. Therefore, it doesnot have extra consumption of electric power. Only by tossing out thepulley rollers through the mechanical centrifugal force, it can cause adisplacement of the inner or outer rotor sleeve, and further change therotational speed of the inner or outer rotor sleeve. With combination ofthe stepless speed change mechanism, it not only has the stepless speedchange function, but also can generate different torque output based ondifferent external loads. Therefore, the present invention has overcomethe disability of existing electric motorcycles to enhance the speed andtorque at the same time. If the existing battery performance is notconsidered, the motor can have limitless output power. Furthermore, itcan directly output the rotational power of the inner rotor through suchtransmission components as belt or chain, and achieve a better heatdissipation effect.

What is claimed is:
 1. A driving device, comprising: a shaft; a pulleydisk assembly, provided on one end of the shaft in a rotatable manner,including a pulley disk and a substrate corresponding to each other, anda plurality of pulley rollers between the pulley disk and the substrate;the pulley disk can move on the shaft; and a motor, configured on theother end of the shaft, comprising an inner rotor and such components asthe stator coil provided on the outer side of the inner rotor; one endof the inner rotor is connected to the pulley disk, while the other endis sleeved on the shaft and is provided with a plurality of permanentmagnets corresponding to the stator coil.
 2. The device defined in claim1, wherein the motor further comprises a casing, provided on the shaftand covering the outside of the inner rotor, while such components asthe stator coil are provided on the inner side of the casing.
 3. Thedevice defined in claim 1, wherein the motor is in the style of apermanent-magnet brushless inner rotor motor.